>>>>> On Wed, 10 Dec 2003 14:08:47 +0100, Dalibor Topic <[EMAIL PROTECTED]> said: >> Do you mean track back to kaffe from where the kernel generates the >> SIGSEGV? robilad> Yes, but it might be a little complicated. I don't really robilad> know how convenient it would be. Especially since you're robilad> trying to debug a stripped kaffe binary in kgdb ... so I robilad> doubt the stacktrace would be very useful, even if you robilad> managed to get it to work.
If you can use kgdb and have some kernel knowledge, finding which instruction causes SIGSEGV is not so difficult. You will have to set some breakpoints at lines which calling functions such as send_siginfo/force_siginfo, etc. with SIGSEGV. If gdb stopped, you can inspect siginfo structure to find out an address of the instruction. Of course you must have disassemble list of kaffe-bin to find corresponding source codes. It is easier to modify your kernel to print this information (just enabling '#if 0' block in arch/mips/mm/fault.c:do_page_fault()). You can even create stacktrace from stack-dump from kernel and the disassemble list, but it will be hard work. >> b) Adding support for gdb stubs for mips to kaffe. There is a >> mips-stub.c in the linux kernel sources [1] and there is some >> documentation on using remote stubs [2]. I do not think it is easy. For example, how to implement breakpoint, single-step, etc? The ptrace system call can not be used to debug itself. I think the gdbserver is the best way. The gdbserver will be not so large (comparing with rt.jar). robilad> Kevin Kissel would be the one to ask. I've CC:ed him as robilad> well. Atsushi Nemoto contributed some fixes for mipsel as robilad> well recently (that I still have to check in, I believe), so robilad> I've CC:ed him, too. Yes, I'm running kaffe on mipsel (Debian). I'm using NFS root and build kaffe natively (not cross-compile). I believe native compiling and debugging is the best way (if possible :-)) I want to make JIT work, but currently no time ... --- Atsushi Nemoto _______________________________________________ kaffe mailing list [EMAIL PROTECTED] http://kaffe.org/cgi-bin/mailman/listinfo/kaffe
